#include <REGX52.H>
#include "Delay.h"

/**
   * @brief  获取独立按键键码
   * @param  无
   * @retval 按键的键码，范围0~4，无按键按下时返回0
   */

unsigned char Key()
{
    unsigned char keynum=0;
	if(P3_1==0){Delay(20);while(P3_1==0);Delay(20);keynum=1;}
	if(P3_0==0){Delay(20);while(P3_0==0);Delay(20);keynum=2;}
	if(P3_2==0){Delay(20);while(P3_2==0);Delay(20);keynum=3;}
	if(P3_3==0){Delay(20);while(P3_3==0);Delay(20);keynum=4;}
	return keynum;
}